Field projects include study of UHP tectonics in Norway, China, Papua New Guinea, and Kazakhstan; ophiolite emplacement in Oman, the Sierra Nevada, and the Klamath Mtns; crustal extension in the Whipple Mtns, the Ruby Mtns, and Crete; formation of continental crust in Tibet, Tajikistan, Alaska, Sierra Nevada, and the Klamath Mtns; collisional orogenesis in Tibet, the Himalaya, and the Pamir.